Question

Currently im “polling”/checking every 1000ms by doing a GET to /moves:

jQuery(document).ready(function() {
setInterval(function() {    
$.get("/moves", function(result){
$('#board').clearBoard();
var myobj = {fen : ""};
myobj.fen = result;
$('#board').chess(myobj); });
}, 1000);
$.ajaxSetup({ cache: false });
})

I want to replace that by updating after I get a POST in a controller:

class MovesController < ApplicationController

def create
 m = Move.new
 last_game = Game.last
 if !last_game.nil? 
   m.game_id = last_game.id
 end
 m.move_data = params[:move_data]
 if m.save
   render :text => "#{m.move_data}"
   **Update JavaScript here**
 else
   render :text => "FAIL"
 end
end


def index
 last_move = Move.last
 if last_move.nil?
   render :text => "FAIL"
 else
   render :text => "#{last_move.move_data}"
 end
end

end

I’m not sure how to do the AJAX/Update from the controller.

Thanks!

Answer 1

The correct way to respond to ajax from the controller is to use a respond_to block. ex:

class MyController < Application Controller

  def my_action
    respond_to do |format|
      format.js # For ajax, which is what you want.
      format.html # For regular html responses.
    end 
  end

end

And then you need a corresponding app/views/my_controller/my_action.js.erb

the respond_to block will detect whether the users browser requested an html file, or a js file (like through an ajax request.)

If you want to do a post to the server, straight from js, I would recommend $.ajax.

The ‘type’ option allows you to specify ‘GET’ or ‘POST’. That method is documented here